Accelerator for dry-pipe valves



April 1930- I F. H. GRlFFlTHS 1,754,511

ACCELERATOR FOR DRY PIPE VALVES Filed Oct. 26. 1925 2 Sheets-Sheet l Inventor.

Francis H. Griffiths MW W April 1930. F. 'H. GRIFFITHS 1,754,511

ACCELERATOR FOR DRY PIPE VALVES Filed Oct. 26, 1923 2 sheets-sheet 2 Fig.2.

inventor.

Francis H. Griffiths b wwkw Patented Apr. 15, 1930 UNITED STATES PATENT OFFICE FRANCIS H. GRIFFITHS, OF YONKERS, NEW YORK, ASSIGNOR TO THE RELIABLE AUTO- MATIG SPRINKLER COMPANY, INC;, OF NEWYORK, N. Y A CORPORATION OF NEW YORK he ACCELERATOR FOR DRY-PIPE VALVES Application filed October 26, 1923. Serial 110.: 670,859.

from the giving way of a sprinkler head, to

admit fluid under pressure to the intermediate or neutral chamber between the water valve and the air valve thereby to partially neutralize the pressure of the air against the air valve and to accelerate its opening movement. One of the objects of the present invention 7 is to provide a novel accelerator which is constructed so that the force which opens the that is normally latched in its inoperative position but which is released upon I a slight rapid fall in pressure in the system." i

Other objects of the invention are toprovide a novel construction in which the auxiliary valve is given a hammer-like blow to open it whenever the accelerator operates thus ensuring a proper opening of the valve even though the latter should be stuck to its seat.

Still other objects of the invention are to improve generally accelerators in various ways all as will be more fully hereinafter set forth and then pointed out in the appended claims. f v r i In the drawings, whereinI have illustrated a a selected embodiment of my invention, Fig. 1 is a view illustrating a dry-pipe valve partly in section and showing the accelerator connected thereto; a

I Fig. 2 is a vertical sectional view through the accelerator;

Fig. 3 shows a modification. r

1 indicates a dry-pipe valve of any suitable or usual construction, it comprising a casing having a waterinlet 2, and an outlet 5 leading to the system, a pivotally-mounted water 7 valve 3 for closing the water inlet, and a pivotally-mounted air valve 4 which is subjected to the air pressure in the system and which operates to hold the water valve closed, said casing having an intermediate or neutral chamber Gbetween the water valve and the air valve. The intermediate chamber 6 norvalve that controls the supply of fluid under pressure torthe intermediate chamber is secured from a weight, springor its equivalent mally has atmospheric pressure therein and the air valve 4 is of sufiicient size so that the pressure thereagainst of the air in the system will serve to hold the water valve closed against the waterpressure.

The accelerators of the type in which this invention belongs are constructed so that when there is a slight quick reduction of pressure in the system, such for instance, as

wouldoccur upon the giving way of a sprinkler head, fluid under pressure will be admitted to the intermediate chamber 6 thus, building up a pressure against the under side of the air valve and accelerating its opening move ment. y y t In the construction herein shown this accelerator comprises a casing 7 which is separated into two chambers 9 and 10 which have communication with each other through a small leak port only. In the present construction this leak port, which is indicated at 11, is formed in the head 12 of a sylphon bellows device 13 which is carried by the partition 14 separating the chambers, the latter having 1 the opening 15 therein communicating with the interior 01": the sylphon-bellows.

The chamber 9 is normally in communication with some source of fluid pressure which may be either the air pressure in the system or the water pressure in the inlet pipe. In the construction shown in Fig. 1 the chamber 9 is normally in communication with the air pressure in'the system and for this purpose it is connected to the discharge 5 through a pipe 16. As the result under normal conditions i neutral chamber 6 is closed by the valve 18.

' In accordance with this invention I have provided an automatically-operative valveactuating means for opening the valve 18 which is normall latched in its inoperative position but which is released whenever there is a slight quick fall in ressure in the system, such as would result from the giving way of a sprinkler head. This automatically-op erative means for Opening the v-valye 18 may be a weight or a spring or any other simliar device. 1 3W? herein lw n a w igh 1.9 f r th 'RPFWWhi hi Qsitivel d inits p rative position. T e weig t has a stem or hanger 20 rising therefrom which is adapted to be supported on a support 22 that is here- 15 in shown as pivoted at eat; the bracket arm 24. The support 2 2 is normally held in the sit-ion shown-in Fig. lby means of a latch 25, said latch being maintained in its operative position by means of a spring 26. The valve 18 is pivotally carried by a lever 27 which in turn is pivoted at 28 'to the bracket member 24 and said lever is shown as acted on by a spring 29 which normallyholds the valve 18 closed. The lever 27 has'an arm 30 extend- ,ga ing therefrom which is situated to be engaged the portion ,31 of the hanger when the weight falls, due to the withdrawing of the latch 25. The construction is such that when the weight is held in its raised position by 30 the latch the loop or portion 31 of the hanger is situated a considerable distance above the lever 27, When, however, the latch 25 is withdrawn from beneath the member 22 then the weight may fall and in :its downward movement the part 31 of the hanger is hrou ht against the lever 27 with a hammerlike low thus opening the valve 18 and allowing fluid nnder pressure to flowtrom the chamber 9 to the intermediate chamber.

. A. construction is provided which becomes operative upon a slight rapid fall in )ressure in the system, such 'as' would result mm the giving way of a sprinkler head, but which will be inoperative upon a slow decrease in s pressure such as might occur b reason of a slow leak in the system, for wit drawing the latch, thus allowing the weight to falland open the valve 18.

The latch 25 is connected to the head 12 go of the syl hon-bellows in such a way that when said 1 ead'moves downwardly, due to an unhalancin of the pressures in the chambers 9 and 10, t c latchwill be withdrawn from en ment with the ar1n 22. ,55 1d latch is shiown as pivotally connected at to one arm 0 a bell crank lever 32 which inturn is pivoted at 33 to the bracket 2ft. The ether-arm ofthe bell cranklever is connected to the head 12, and-thus a 'downwardmove ,60 ment'of-the-head' 12 will operate through the bell crank to retract the latch 25.

Under normal conditions the pressure in thetwo-chambers 9 and 10 will be equalized because of the prese ceof theleak port 11 and .135 the latch-2 5 -will bfh ld maintained in its operative position by the spring 26. If there is a quick drop in pressure in the system due to the giving way of a sprinkler head then the pressure in the chamber 9 will be correspondingly reduced but the pressure in the chambe wi l b duced only slowly due to the smallness of thehperture 11. As a result the pressures against the opposite sides of the head 12 will be unbalanced and the latter will more down ardly thereby operatin th ug t e le e 3 t withdraw the lat 25 from engagement with the arm 22 This releases the weight 19 which falls and by its engagement with the lever 27 opens the valve 18 thusallowing'air under pressure in the chamber 9 to be delivered to the intermediate chamber 6 which results in accelerating the opening movement of the air valve 4.

An advantage of this construction is that when the accelerator operates the Valve '18 is given a hammer-like blow by the falling weight 19 with the result thatany tendency for the valve to stick is instantly overcome and the proper opening of said valve is ensured.

An important feature of the invention is that the force necessary to open the valve 18 is not derived directly from the movement of the member 12 due to the unbalancing of the pressures thereagainst but is derived from the falling weight 19.

lnstead'ol connecting the chamber 9 with the s 'stem as shown in Fig. 1 this chamber may e connected with the Water supplypipe as 'show'n'in Fig, 3, in which case the fluid under pressure which is admitted to the intermediate chamber will be water from the water main rather than air from the system. The operation of the device, however, will be thesame in either instance. v

I claim:

V 1. An accelerator for dry pipe valyescomprising a casing, a sylphon' bellows within the casing dividing the latter into two cha n- 'bers, said sylphon having a restricted orifice forming a restricted communication between the chambers, means connecting one chamber to the system side of a dry pipe valve and also connecting said chamber to the neutral chamber of said valve, a valve normally closing the latter connection, a weight which by its fallin movement opens "the valve, means inclu ing sending spring-pressed latch for normally holding the weight elevated, and a connection between said latch and the sylphon'bellows, whereby a reduc- ,tion of pressure on the system side of the dry pipe valve will cause the sylp'hon bellows tdacthate the spring-pressed latch and re 'lease. the weight An accelerator for dry pipe valves compr sing a casing, a syl hon bellows .vvithin the casing dividing the atter into two chambers, said sylphpnhaving a restricted orifice the chambers, means connecting one chamber to the system side of a dry pipe valve and also connecting said chamber to the neutral chamber of said valve, a valve normally closing the latter connection, a sliding spring-pressed latch connected to said bellows, a pivoted weight-supporting member having its free end normally engaging said latch, and a weight normally supported by said weight-supporting member and which by its falling movement opens said valve, whereby when a reduction of pressure on the system side of the dry pipe valve occurs the bellows will withdraw the latch from the weight-supporting member and thus release the weight.

3. An accelerator for dry pipe valves comprisinga casing, a sylphon bellows in said casingand separating the latter intotwo chambers, means connecting one of the chalmbers to the system side of the dry pipe valve, other means connecting said chamber to the neutral chamber of the dry pipe valve, a valve controlling the latter connection, a sliding latch, a pivoted elbow lever connected to said latch and to said sylphon, a pivoted weight-supporting member normally engaging said latch, and a weight supported by said member, whereby when the pressure between the chambers becomes unbalanced the expanding action of the sylphon withdraws the latch from the weight-supporting member allowing the weight to fall and open the valve in the connection leading to the neutral chamber of the dry pipe valve.

4. An accelerator for a dry pipe valve comprising a chamber normally containing fluid under pressure and provided with a communication leading to the neutral chamber of a dry pipe valve, a valve normally closing said communication, a weight which by its falling movement opens the valve, a pivoted weight-supporting member on which the weight is supported, a sliding latch normally engaging said member and holding the weight raised, and means rendered operative by a slight rapid reduction of pressure in the system to withdraw said latch from said support and allow the weight to fall.

In testimony whereof, I have signed my name to this specification.

FRANCIS H. GRIFFITHS. 

